1. Field of the Invention
The present invention relates to an auto focusing light device for use with an auto focus detecting device for a TTL camera.
2. Related Background Art
A photoelectric conversion element array of an auto focus detecting device for a TTL camera is normally disposed unidimensionally at a position optically equivalent to the vicinity of the center of a film (in the vicinity of the optical axis of a lens) in the longitudinal direction of the film. To guide the object light into the element array, the object light which has been transmitted through the lens is conventionally guided via a semitransmissive portion of a main mirror and a supplementary mirror, or via a reflecting mirror.
In detection of the focus by the auto focus detecting device of a camera, no problem is presented when the object is of adequate brightness. However, if the object is dark, the focus detection time may become extremely long, or detection of the focus may become impossible.